1. Field of the Invention
The invention relates generally to the field of photography and more particularly to an electromagnetic control device for use in a camera or the like to control a function of the camera.
2. Description of the Prior Art
Typically in cameras, it is known to include an electromagnetic control device for controlling one or several functions of the camera, such as shutter timing or lens focusing. The accuracy of each function greatly depends upon an intimate face-to-face contact of the attracting face of a magnet core and the attracted face of an armature which is usually pivotally connected to a control lever, as in U.S. Pat. No. 4,342,018, granted July 27, 1982, U.S. Pat. No. 4,360,258, granted Nov. 23, 1982, and U.S. Pat. No. 3,762,297, granted Oct. 2, 1973.
When the attracting face of the magnet core and the attracted face of the armature are not in perfect face contact, the attracting force acting between the two faces is markedly lowered and there is a possibility of a malfunction of the control lever. At worst, there is the possibility that the armature will move apart from the magnet core before the magnet core is demagnetized. Furthermore, there is the possibility that the timing of separation of the armature from the magnet core will not be accurately controlled.
The imperfect face-to-face contact between the attracting face of the magnet core and the attracted face of the armature is caused generally by errors in mounting the various elements of the control device, and it often occurs when there is a need for the control lever to overtravel to a particular position after the two faces are brought into face contact.